PTL 1 discloses a communication system using an IIC (Inter-Integrated-Circuit) bus (also known as I2C bus). The I2C bus is a 2-wire low-speed interface, and is used as a bus for managing various kinds of information processing apparatuses such as computers, for example an on-vehicle computer, a network apparatus, a hand-held device.
PTL 2 discloses a system having an input/output module doubled. In the system, an input from the process is received by both operation and standby I/O (Input/Output) modules, but an output to the process is performed only by the operation I/O (Input/Output) module.